Motor vehicle



Sept. 7,1937. YM. AITKENA A, 2,092,040

MOTOR VEHICLE ATTORNEY- E @966/ T A Sept. 7, 1937. M. AITKEN 2,092,040

i I MOTOR VEHICLE Filed Nov. 5, 1935 5 Sheets-Sheet 2 IN V EN TOR.

Maffay Al/Ken M. AITKEN MOTOR VEHICLE Sept. 7, 1937.

Filed Nov. 5, 1935 3 Sheets-Sheet 3 INVENToR. Maf/fai /UW TOM/j. l

associated drive mechanism Patented Sept. 7, 19537 UNITED .STATE Moron. vement M'umy Aitken, seattle,

worth Motor Truck Corporation, a corporation of Washington Wash., aasignor to Ken- Scattle. Wash.,

Application November 5. 1935. serial Nassau `f 9 Claims.

My invention relates to motor vehicles and particularly to that character of vehicle in which the drive or power unit is disposed to the rear of the differential assembly, the invention being directed toimprovements over the structural arrangement disclosed in the. pendin'g patent ap,I plication of Lloyd A. Mallett, led November 6th, 1934, Serial Number 751,723.

Similarly to .the pending application above identified, the present invention aims to provide. a more compact assembly of the power plant and than has previously been obtained whereby to reduce thel over-all length of the assembly and additionally/.purposes to eieet a lowering of the overall height and generally eiect a more advantageous association r of the cosactive parts tov-,render the parts stronger and more accessible, i Dillicultiesv encountered in cooling motor unitsmounted inthe rear of a vehicle has been a prime deterrent to the use of this character of motor assembly and it is a further and particular object to devise a cooling arrangement peculiarly designed to overcome these objections.

Further objects and advantages, together with the foregoing, will become apparent inthe course of the followingv detailed description and in the claims annexed thereto, the invention consisting in the novel construction, adaptation, and combination of parts hereinafter described and claimed.

In the drawings: j

Figure 1 is a fragmentary top plan view representing the now preferred embodiment of the invention, the frame and body of the vehicle forwardly of the rear wheels being omitted and that portion of the body designed with especial reference tothe power plant assembly being shown in horizontal section. Fig. 2 is a longitudinal vertical section taken on the section line 2--2 `of Fig. 1. Fig.'3 is a detail Aside elevation of the rear end ofthe vehicle, taken to areduced scale.

Fig. ,4 isa transverse vertical section taken on the lined- 4 of Fig. 1; and

Fig. 5 is a detail transverse verticaLsection taken o n the line 5-5 of Fig. 1 to indicate the transfer gear-and-chain employed between the power plant and the transmission. Y In carrying out the invention, reference being had to the drawings, the numeral 6 indicates the rear wheels of arvehicle of lthe passenger-bus character in which the rear seat is disposed to overlie the differential housing 1, the differential housing being of conventional design except coupled to the vehicle'yframe ster members, the bar power plant vpair of transversely spaced and horizontally (ci. iso-@54) f that the-same is reversely disposed and located in laterally oit-set relation tothe longitudinal center line of the vehicle. As in ordinary practice, the tube extensions for the axlewhich lead from the differential to the wheels -6 are resiliently by springs 8 and the coupling rods Blylng between the spring en ds and the frame being disposed transversely across the vehicle frame. The vehicle frame, employing welding, is constituted of longitudinal channel members I0 having arched kick-ups Il extending over thefaxle housings with ,channel extensions I2 projecting rearwardly from the kick-ups to the rearv` limits ofthe vehicle, a transverse channel I 3 at the rear endof the vehicle acting together with a bar I4 of'an inverted-V form as frame holsters for the vchannelextensions. I2. Said bolil being located in proximity oi' but spaced slightly to 'the' rear ofthe differential, operate in conjunction to support a such as indicated by i5, the front mounting for said power plant comprising an annular collar supported by the b'ar I4 `to off-set the motor laterally from the longitudinal median line of the vehicle frame to the side opposite that of the differential and the rear being bolted`with the mounting compris Having particular reference to the'power plant assembly, the motor I5 of which lies horizontally or nearly horizontal in a longitudinal vertical plane oiI-set from the median line of the vehicle, a conventional clutch and housing 20 therefor are supported between the motor andthe transfer case Il. Housed by said transfer case are a aligned sprocket wheels 2I and 22 (Fig. 5) which operate through the median of a silent chain 23 to transfer power from the motor through the gears of a transmission assembly to a torque shaft 24 which connects with the differential gearing, the transmission being carried in a housing 25 laterally spaced fromthe motor and disposed forwardly of the transfer ease in the longitudinal I vertical plane of the differential'.v Conventional tol uence of respective rods 21 extending forwardly lo over the inner end of the differential housing to engage the upper arms of levers fulcrumed as at 28 to the vehicle frame, the lower arms of the fulcrumed levers connecting with control rods 29 which extend to the drivers compartment for l5 operation by a. gear-shifting lever (not shown).

In the cooling system for the motor is a conventional radiator 30 which is mounted in the approximate transverse vertical plane of the transfer case on a floor 3l carried by the second- 20 ary frame of the vehicle which lies on the transmission side of the motor assembly.` This `supporting floor preferably lies ush with the upper surface of the frame members I2 and, for bracing the radiator, a strut 33,of a general L shape 25 is brought upwardly-and over the' radiator from the angle-iron I9, the horizontal arm of the strut being anchored to a vertical forward wall 3|' disposed to the rear of the vehicle wheels 6. Hose connections, as 34, extend from the radia- 30 tor to the water jackets of the motor with the water pump being carriedA at the forward end of the motor in -the path of circulation of the water through the water jackets. i

Indicated byv35-and 35' are the side and rear 35 body walls of the vehicle and provided thereby to obtain circulation ofair through the motor compartment are screened openings 36 and 36', the body side wall which lies adjacent the radiator being provided along the rear edge of the 4o 'screened opening with an exteriorly disposed hood 3l protruding slightly from the surface of the vehicle body to trap air in directing the same through the opening. Between said opening and the radiator, I provide a tunnel 38 shielded 45 from the motor compartment. Circulation of air through the tunnel is influenced by a fan 40 carried by the strut 33I to locate the fan to the rear of the radiator whereby a certain degree of air circulation is obtained through the screened 50 opening lying at the opposite side of the compartment.

To obtain a circulation of air through the motor compartment in advancing the radiation of. heat from the walls of the motor, I have devised 55 an especially effective arrangement which peculiarly co-acts with the shielded tunnel in that it offsets the loss of air circulation normally drawn by the fan over the motor, the arrangement consisting in providing a depressed pan 4I 60 under the motor extending between the frame channels l2 in a plane below that of the forwardly disposed passenger oor 42, the space about the axle' and differential housings between the forward lip of the pan and the floor level of the 65 vehicles passenger compartment defining a relative air funnel. Said air funnel, under the iniiuence of vehicle momentum, acts to force a current of air past the motor.

by the sprocket wheel 22. Suitable take-ups for the belts are shown at 49 and 50.

While not shown in the drawings, the body vwall to the rear of the motor compartment isl f vehicle frame, said frame providing longitudinal- `ly spaced transverse bolsters to the rear of. the

rear axle assembly, a motor supported by said bolsters to extend longitudinally of the vehicle in a plane off-set from` the central longitudinal line of the frame to the side opposite that of the differential, change-gear mechanism disposed laterally of the motor in the longitudinal line of the diierential, connection from.the'rear end of the motor to therear end of the change-gear mechanism, and connection including universals from the forward end of the change-gear mechanism to the differential. l

2. In a rear-drive motor vehicle, in combination with a rear axle assemlbly including a reversely disposed differential off-set from the central longitudinal line of the vehicle, and a vehicle frame including lateral girders projected longitudinally of the vehicle and extending rearwardly of. the rear axle assembly, said rearwardly extended portion of the vehicle frame having longitudinally spaced transverse bolsters extending between the girders, aimotor, a power transmitting assembly for said motor comprising change-gear mechanism disposed laterally of the motor and transfer mechanism extending transversely from the rear end f vthe motor to the rear end of the change-gear mechanism,

. housings for said change-gear and transfer mechanism connected one with another and with the motor block, connections between the forward end of the motor and the forward bolsterand between the housing for said transfer mechanism.

the 1ongaudma1 une of the dinerential, nexible drive connection between said change-gear mechanism and the differential, a motor disposed laterally of the change-gear mechanism and off-Set from the longitudinal center line of the vehicle y to the side opposite that of the differential, said Motor accessories such as an air compressor 70 and a generator are indicated at 43 and 44, said motor having its power-Output end directed conversely to that of the change-gear mechanism, and transfer mechanism from said power-output end of the motor to the change-gear mechanism.

4. In a rear-drive motor vehicle, in combination with a rear axle assembly including a reversely disposed differential, a motor, changegear mechanism, means supporting said motor and change-gear mechanism to locate the same td the rear of the rear axle assembly in parallel planes disposed laterally of one another and with the change-gear mechanism lying in the longitudinal line of the differentiaLfadrive connection including universals from the forward end of the change-gear mechanism to the differential, and a drive connection comprising transfer mechf anism extending transversely of the vehicle for connecting th rear end of the motor with the rear end of the change-gear mechanism.

5, In a rear-drive motor vehicle, in combination with a rear axle assembly including a reversely disposed differential off-set from the central longitudinal line of the vehicle, and a'vehicle main frame including lateral girders projected longitudinally of the vehicle and rearwardly of f the rear axle assembly and provided to the rear of said rear axle assembly with longitudinally ential, secondary frames to the rear of the rear axle assembly at each side of the vehicle main frame, a radiator supported by the secondary frame lying to the change-gear side of the vehicle, connection from the radiator to the motor.

a vehicle body providing walls at each side and.

to the rear of the vehicles rear extension having screened openings kfor the circulation of air through the motor compartment deiined by the walls, a shielded tunnel leading tothe radiator from the opening in the side wall adjacent 'the radiator, an exterior hood to the rear of the opening for trapping air passing the opening under the influence of vehicle travel. and a motor-driven fan mounted to the rear of the radiator for drawing the trapped air through the tunnel and the core of the radiator.

6. 'I'he structure as dened in claim 5 wherein the motor compartment is open at its forward end and between the side girders is provided With a pan extending below the motor assembly to obtain a forced circulation of air under'the iniiuence of vehicle travel into the forward end of the-motor compartment to co-act with the fan-induced current `oi'air in cooling the motor.

7. A frame for a rear-drive motor vehicle in` which the motor is mounted tothe rear of the rear axle assembly comprising a main frame including longitudinally extending lateral girders disposed interiorly of the longitudinal lines of the vehicle wheels and projecting to the rear of the rear axle assembly a distance approximating the length of the vehiclemotor, a motor-supporting bolster of a general inverted V shape at the forward end of said rear extension projected transversely across the girders, a rear motor-supporting bolster comprising ahorizontal member extending the width of the vehicle atthe rear limits of the side girders,' and horizontal brace members extending outwardly from said side girders at the forward end of the rear extension to coact with the lateral extensions of the rear bolster in forming secondary frames at each side of the rear extension of the vehicles main frame.

8. In a motor vehicle of the character in which the motor is mounted to the rear of the rear axle, the combination with a rear axle assembly y includingja reversely disposed differential, Aand a vehicle body providing a motor compartment to the rear of the rear axle, a motor and power transmitting mechanism supported in said motor compartment and connected with the differential vfor driving the rear axle, screened openings in the rear wall and a side wall of the motor compartment, a Water-cooling system for the m'otor including a radiator supported within the motor compartment in laterally oil-set relation to the motor, a tunnel shielded from the motor compartment and leading to the radiator from the `side-Wall opening, a motor-driven fan for drawing air through said tunnel to cool the radiator, and means operating under the influence of vehicle travel to obtain a forced circulation of air over the motor to co-act with the water-cooling system for cooling the motor.

Q. In a motor vehicle of the character in which the motor is mounted to the rear of the rear axle, the combination with a rear laxle assembly providing a lreversely disposed differential, and a vehicle body providing a motor compartment to the rear of the rear axle, a motor and powr transmitting mechanism supported in said motor compartment and connected with the differential for driving the rear axle, -screened openings in the rear wall and a side wall of the motor compartment for admitting cooling air to and delivering heated air from the compartment, re- 

